Building codes today require that certain walls or, more commonly, sections of walls, of wood or steel framed houses or buildings, be formed to resist lateral (shear) loads due to anticipated seismic or wind conditions. Typically, ⅜″ to ⅝″ plywood sheets have been installed on the interior or exterior side of the framing studs to accept such lateral loads. It is common practice to install ½″ inch to ⅝″ thick wallboard panels (“drywall panels”), such as gypsum wallboards, on the interior sides of the framing studs and a ¾″ plaster (stucco) finish or other suitable material (with a water barrier) on the exterior side of the framing studs. Such interior and exterior finishing materials are typically installed over any plywood panels providing the lateral load resisting capacity. It is customary to install the plywood panels across an entire wall, requiring shear load resisting capacity, whether the plywood panels are located on the inside or outside of the framing studs, even when not needed in certain areas of the wall to avoid a drastic change in wall thickness.
For example, the interface between a ½″ drywall panel overlying a ½″ plywood panel and an adjacent sheet of ½″ or even a ⅝″ drywall panel would require considerable furring. By the same token, ½″ plywood paneling covering only a portion of an exterior framed wall would result in reducing the thickness of a typical exterior ⅞″ plaster finish by ½″. Such a thin layer of plaster is undesirable in that it will crack or break. 
This current use of plywood to form a shear wall is wasteful of a limited natural resource. In addition, when subjected to reverse cyclical lateral forces (now required by the Uniform Building Code for shear wall structures) the openings in the plywood through which the fasteners (nails or screws) are placed tend to enlarge thereby tending to reduce the lateral load resisting capacity. In addition, plywood sheets are normally available in 4′ width and 8′, 9′ or 10′ lengths. An interior or exterior shear wall often requires a panel length that falls between such standard lengths, resulting in scrap end pieces.
As an alternative to using plywood sheets, steel straps have been installed in an “x” configuration to the wall framing studs, i.e., cross bracing, to provide shear resisting capacity. The interior drywall or exterior finishing material is then attached over the steel straps. Such straps generally require special plate brackets and are difficult to install without resulting in a sagging or loose fit. While the steel straps need only be employed in desired locations along a frame wall, if employed on the interior sides of the studs, there may be undesirable bumps or bulges in the inner wall surface. Further, such a wall structure is labor intensive to construct and requires higher design loads as specified by the building codes.
One solution to the above problem is disclosed in U.S. Pat. No. 5,768,841 (“'841 patent”) which issued to two of the co-inventors of this application. The '841 patent describes a composite wall board panel in which a thin sheet of high strength material, such as steel, is bonded to a wallboard panel made, for example, of gypsum. The overall thickness of the laminated panel, marketed as SURE-BOARD®Series 200 under the patent, is ½″ or ⅝″. SURE-BOARD is a trademark of Swartz and Kulpa Engineering. The 200 panel provides adequate lateral load protection for a section of a wall and eliminates a change in wall thickness when abutting a conventional drywall panel. While the 200 panel may be installed on steel studs as well as wood studs it is more readily attached with drywall screws which have a bugle head allowing the top surface of the screw to be set flush with the surface of the installed panel, therefore accommodating conventional taping.
Screws adapted to penetrate the steel sheet are generally hardened and when used to fasten the panels to wood studs may tend to break at the wood/steel sheet interface, e.g., by fatigue, when exposed to repeated shear forces thereby degrading the shear load protection. Such breakage may not be apparent without a partial destruction of the wall. In addition, the 200 panels are designed primarily for interior installation.
We have found an improved method of forming a shear wall structure in a stud framed building which is particularly adapted for wood framed structures and capable of forming a shear wall on the interior or exterior side of the framing studs. Our improvement includes the discovery of a novel, thin, subsurface, steel laminated, panel (hereinafter “subsurface shear panel” or “shear panel”), particularly useful in carrying out the method.